General contractors on both large and small construction projects may have requirements to specify invoices/billing for selected subcontractors. According to this practice, known as “specified billing,” the general contractor specifies the value of the work completed by a subcontractor directly without input from the subcontractor. Other situations also require a party (e.g., a general contractor, a parent subcontractor, a quantity surveyor, or an owner) to specify the value of the work completed by one or all of the contractors working on the project (e.g., a payee). For example, on some construction projects (such as projects with unit pricing), the payor may hire and/or employ an inspector who “measures” or surveys the units completed for the project and calculates how much will be paid. In these and other situations, the payee and/or the payor may by contract or by practice be given limited or no ability to adjust how much will be paid.